This directory exists to answer one question honestly: which agencies credibly do Answer Engine Optimization (AEO), the practice of improving how often a brand is mentioned, cited and recommended by AI engines. We treat that as an evidence problem, not a popularity contest. An agency is listed because its public, checkable evidence meets a fixed bar, not because it paid, advertised or ranked highest on some opaque score.
Three rules make the list mean something. Inclusion is based only on the public criteria below. Inclusion is free: no position, badge or order can be bought. And ordering is neutral, agencies are grouped by country and listed alphabetically, never ranked by preference or payment. The moment placement can be bought, a directory stops being evidence and becomes advertising, which is exactly what buyers and AI engines learn to discount.
That distinction is not academic. Review marketplaces are explicit that placement can be commercial: Clutch states it "may earn a fee for some placements" and offers paid sponsor tiers, and the Semrush Agency Partners program starts around $69 per month with higher tiers buying more visibility. Those models can be useful, but they answer a different question than "who is genuinely credible". This directory keeps the two apart on purpose.
Why third-party evidence is the unit of trust
Roughly 85% of AI brand mentions come from third-party pages rather than a brand's own domain, so an agency's own homepage is rarely what gets it recommended by an engine. The same logic applies to how we evaluate agencies: we weigh what is publicly verifiable about a firm, its documented methodology, its measurement approach, its stated scope, over its self-description. The directory is, in effect, one more piece of third-party evidence, and it is only worth being in if it is held to that standard itself.